Immunization with E. coli produced recombinant T. gondii SAG1 with alum as adjuvant protect mice against lethal infection with Toxoplasma gondii

Vaccine. 1998 Aug;16(13):1283-9. doi: 10.1016/s0264-410x(98)00039-5.


Polyclonal rabbit antibodies against recombinant Toxoplasma gondii SAG1 antigen expressed in E.coli recognize T. gondii and the antibodies significantly reduced T.gondii adherence and/or invasion into the host cell as did a monoclonal antibody against a conformational epitope of the SAG1 antigen. Groups of outbread NMRI mice were immunized with recombinant T. gondii SAG1 antigen in alum. The antibody response to immunizations was dominated by a Th2 response with production of T.gondii specific IgG1 antibodies. Challenge with tachyzoites from the virulent RH-strain produced a Th1 response dominated by the production of specific IgG2a antibodies and moderately boosted the IgG1 response, and challenge with bradyzoites from the avirulent SSI119-strain showed the same pattern. Immunization with rSAG1 resulted in a significant increased survival after challenge with tachyzoites of the RH-strain. Immunization with E.coli expressed recombinant SAG1 in alum induce partial protective immunity against lethal infection with T. gondii in mice.

MeSH terms

  • Adjuvants, Immunologic / therapeutic use*
  • Alum Compounds / therapeutic use*
  • Animals
  • Antibodies, Monoclonal / immunology
  • Antibodies, Protozoan / biosynthesis
  • Antibodies, Protozoan / immunology
  • Antigens, Protozoan / immunology
  • Antigens, Protozoan / therapeutic use
  • Antigens, Surface / immunology
  • Antigens, Surface / therapeutic use
  • Bacterial Adhesion / immunology
  • Escherichia coli
  • Fluorescent Antibody Technique
  • Immunization
  • Immunoglobulin G / biosynthesis
  • Mice
  • Protozoan Proteins / immunology*
  • Protozoan Proteins / therapeutic use
  • Protozoan Vaccines* / immunology
  • Rabbits
  • Toxoplasma / immunology*
  • Toxoplasmosis, Animal / prevention & control*
  • Vaccines, Synthetic* / immunology


  • Adjuvants, Immunologic
  • Alum Compounds
  • Antibodies, Monoclonal
  • Antibodies, Protozoan
  • Antigens, Protozoan
  • Antigens, Surface
  • Immunoglobulin G
  • Protozoan Proteins
  • Protozoan Vaccines
  • SAG1 antigen, Toxoplasma
  • Vaccines, Synthetic
  • aluminum sulfate